Sealpit stock saver



May 31, 1932. H. e. CRAM S EALPIT STOCK SAVER Filed Sept. 24, 1931 Imrezziom:

Hervey a. ram

Patented May 31 1932 UNITED STATES? HERVEY e. 01mm, or sucxsronr, MAINE, AssIGnon TO MAINE seasonal rarnncom: PANY, or :eucxsroa'r, MAINE,- nsconron'arrouor -MAINE,

SEALPIT sTocK'sAvER i Application filed September24,; i931. Seria1 Nc.564,812.

of the invention is to provide a construction permitting the free utilization of the filtrate as desired without waste and without adversely afiecting the operation of the filter' mechanism.

My invention finds a particular application in the papermaking industry andfor convenience I shall specificallyrefer to such application in the following descriptionfrom which, when taken in. connection'with the accompanyingdrawings, my 1nvent1on may be well understood. In these drawings Fig. 1 is a partial plan view of the sealpit; Fig. 2 is a section on the line 22 of Fig. 1 with parts broken away; and

Fig. 3 is a fragmentary section on the line 33 of Fig.2.

Referring to Fig. '1 of the drawings,l have there shown a sealpit 5 which in this case is a concrete tank situated on the floor beneath mechanical filters. The filtrate or discharge 4 through the wire mesh of the cylinder passes downward to the sealpit through the barometric'legs 7 and .9, the lower ends of which are submerged in theliquid retained in the I sealpit, thus providing for a vacuum or suction in these legs. In the manufacture of paper this filtrate has a very considerable Value asa certain proportion of finer fibers will pass through the wire mesh with the filtrate into the sealpit. Therefore, in paper mill filtrate as possible for thinning stock, etc.

It will be appreciated, however, that if an undue amount of thefiltrate is drawn off at any given time the level in the sealpit may fall below the bottoms of'the legs7 and 9 breaking the vacuum. f I Heretofore it has therefore been customary to supply freshwater to the sealpit to maintain a predetermined level by establishing an overflow over a suitablejweir" or dam. The excess water running over the dam, however,

carried with it a considerable amount of the stock in the filtrate resulting in waste. The construction which Iam about to describe obviates this difficulty; I I have herein shownzas constructed 'adja:

place of utilization. Provision is" made .cent to, herein, within the outlines of the tankl5, achamber 11 to which make-up water is supplied by pipe 13, a constant level being maintained in the chamber 11 higher than the bottomfofthe legs 57 and;9, this herein being efi'ectedby providing an joverfiow at passage 17to the sewer ,orto anyconven'ient whereby make-up water may flow'from the chamber ll'to the: sealpit. proper as the level of thefiltrate inlthe latter falls to: such an extent as to endanger the vacuum in the barometric legs while on. the other hand flow from the sealpit tov the chamber and hence its waste over the damis prevented. For this purpose the walls of the chamber 11 are provided with suitable Openings 17 closed by the swinging gates 19 which open away from the chamber and toward the sealpit and which constitute essentiallycheck valves permitting.

flow from the chamber to the sealpit but preventing flow in .thereverse direction. The r r bottoms of these gates, as seen by Fig. 2, are beneath the level defined by the crest of the weir or dam 15.

Itwill thus be seenthat if the level of the filtrate inthe sealpit is high, water will flow into the chamber 11 and over dam 15, mainting water to flow into the sealpit to maintain the level and prevent breaking of the vacuum in the legs. If the level of the filtrate in the t ythe checkvalve gates l9 will open permitpractice it is desirable to use as much of this sealpit becomes higher than the level of the I andhence over the dam to the sewer to be Wasted.

I am aware that the invention may be embodiedin other specific forms without departing from the spirit or' essential attributes thereof, and I therefore desire the present embodiment to be considered in all respects as illustrative and not restrictiveereference being had to the appended claims rather than i to the foregoing description to indicate the sco e of the invention.

laims: 1. In combination with the sealpit and barometric leg discharging thereto, a. chamber adjacent to the sealpit having means for maintaining a level ofwater therein above the bottom of said leg and check-valve means between the chamber and pit opening toward 2. In combination with a sealpit, a barometric leg through which fluid is su lied thereto means to supply make-up flui and means effective only when the fluid in the sealpit falls below a determined level to admit fluid from said supply to the pit.

3. In combination with a sealpit, a barometric leg through which fluid is supplied thereto, a tank having an overflow at a level above the bottom of said leg, means to supply make-u e fluid to ,said tank and a one-way connection between the tank and pit through which fluid may flow from the former to the latter when the fluid in the latterfalls below a determined level. a I p "In testimonywhereof, I have signed my name to this specification.

' 'HERVEY G. CRAM. 

